Mineral water has been used for a long time for preparing drinks in feeding bottles for infants, which generally comprise a nipple removably fixed to a bottle with a wide neck by means of a threaded ring adapted to be screwed on to said neck. The ring and the nipple after being fitted on the bottle form a liquid tight end-piece which allows air to enter the feeding bottle, progressively as the infant sucks. The bottles and the threaded end-pieces are sterilized before the feeding bottles are filled, including those to be filled with mineral water which are frequently given to a young child during walks, journeys or similar outings. It is then necessary, during such outings, to take one or more sterilized nipple bottles and the mineral water bottles for filling them. The weight and space required, particularly for a young mother, may then be a hindrance.